ok. it's a 90 renix 4.0 had ot for a 2yrs, no probs. it' been very pampered, garaged, not abused, all stuff kept up, and never a problem. Today I take it to get it's DPS yearly inspection, all works well, and I get new wipers. When I try to leave, the engine turns over, but won't start. Check fuses, and all wires. I have juice to the coil but no apparent juice to the plugs. Tow it home, check the fuel press. at the shraeder valve and it's got fuel. So I pull a plug wire and hook up a light to see if there is spark. when I turn the engine over IT STARTS!!!! WTF. HOOK up the plug wire and it runs just like new. Question is "what caused the no start earlier" any body please any body gie me your thoughts. Thanks.

 

CPS could be going out. Or the ETC. NSS could also be a culprit

 

Test your CPS

Renix CPS Testing and Adjusting
　
　

Renix CPSs have to put out a strong enough signal to the ECU so that it will provide spark.

Most tests for the CPS suggest checking it for an ohms value. This is unreliable and can cause some wasted time and aggravation in your diagnosis of a no-start issue as the CPS will test good when in fact it is bad.

The problem with the ohms test is you can have the correct amount of resistance through the CPS but it isn’t generating enough voltage to trigger the ECU to provide spark.

Unplug the harness connector from the CPS. Using your voltmeter set on AC volts and probing both wires in the connector going to the CPS, crank the engine over. It won’t start with the CPS disconnected.

You should get a reading of .5 AC volts.

If you are down in the .35 AC volts range or lower on your meter reading, you can have intermittent crank/no-start conditions from your Renix Jeep. Some NEW CPSs (from the big box parts stores) have registered only .2 AC volts while reading the proper resistance!! That’s a definite no-start condition. Best to buy your CPS from Napa or the dealer.

Sometimes on a manual transmission equipped Renix Jeep there is an accumulation of debris on the tip of the CPS. It’s worn off clutch material and since the CPS is a magnet, the metal sticks to the tip of the CPS causing a reduced voltage signal. You MAY get by with cleaning the tip of the CPS off.

A little trick for increasing the output of your CPS is to drill out the upper mounting hole to 3/8" from the stock 5/16", or slot it so the CPS bracket rests on the bell housing when pushed down. Then, when mounting it, hold the CPS down as close to the flywheel as you can while tightening the bolts.



　

　

Revised 01-26-2013

 

Even the Harbor Freight $5 Digital Meter works!, (at least for a while)